Tag Archives: quantum dots

Light-emitting diodes (LEDs) are highly efficient, but they can’t directly produce white light. Though a blue LED can be coated with a phosphor that alters some wavelengths to yield a whitish mix, the resulting light has a bluish cast, and some energy is wasted as heat in the process. A new LED lamp avoids this problem by using an optic coated with quantum dots–bits of semiconductor material a few nanometers in diameter. When excited by a light source, the dots radiate light in wavelengths that vary according to their sizes. The optic–coated with dots in specific sizes and ratios–appears orange when the light is off (left) but radiates white light when the underlying blue LED is on (right). The result: LED lamps that are 50 percent more efficient and produce better-quality white light.

Because the Nexxus Lighting Array lamps with Quantum Light™ are compatible with a standard, screw-in Edison base, they can easily replace incandescent and halogen lamps in existing downlight fixtures. Just in the US, the DoE estimates, the number of down lights and track heads with Edison base lamp installations equal over 139 million in commercial applications and over 262 million in residential lighting applications. Both companies expect that commercial availability of their high efficiency lamps with high color quality will overcome a major barrier to LEDs and will accelerate the penetration of LEDs in the $4 billion U.S. lamp market. The potential impact on the environment could be significant, a full conversion to LEDs of existing downlights and trackheads in the US (approximately 10% of US fixtures) represents an annual savings of more than 35 billion KW hours (nearly $4 billion), which is the equivalent of nearly 6 power plants or more than 60 million barrels of oil per year.